Drones in Construction and Earthworks
Australian construction, road and rail works.
Drones and their application is a popular topic many Australian business. The construction industry were early adopters of drones. The industry has been using them and other unmanned vehicles to provide a range of services since 2013.
The application and use of drone technology in the construction industry falls into three main categories; survey, progress monitoring, and asset inspection. Each of these applications require specialist knowledge and technology.
The following will focus on the drone survey applications.
The movement of large volumes of the earth is an essential part of construction. The logistics, engineering effort and equipment is considerable. The correct planning, scheduling, and supervising of earthworks operations are important to the project’s success. This is one area where the application of unmanned technology can deliver real value.
A purpose built survey drones has the capacity to survey large areas quickly, accurately and affordably by acquiring survey data from large areas covering around >30ha in 30minutes. Further, a survey drone can recapture exactly the same data at a different point in time. The large area coverage, repeatability and accuracy is valuable to any project that has a spatial component such as commercial construction, infrastructure, rail and road.
The results of drone surveys can be used by project managers, logistics teams, compliance officers, safety managers and auditors to conduct a range site assessment tasks. An example of earthwork computations and haulage logistics is given below.
Earthwork computations and haulage logistics using drones
“You can’t manage what you can’t measure”
It is an essential part of projects shifting large volumes of earth to have a haulage plan. Haulage plans are only as good as the data and measurements that sit behind them – like earthworks computations. Current surveying methods use a combination of Global Navigation Satellite Systems (GNSSs) and total station surveying methods to assess the volumes of earthworks and to plan the excavation, removal and placement of material. This method is time-consuming and the pointwise selection often yields omission errors due to surface unevenness in-between the consecutive survey points (Sobak, Ellmann, & Mill, 2015). This is compared with drone photogrammetry techniques which collects thousands of surface points and creates an accurate 3D representation of the land surface. Volumetric calculation then considers every detail and imperfection. Using drones for volumetric survey means is there is no requirement to install and maintain survey points.
The below images are from Julge, Ellmann and Köök’s 2019 article on the application of this technology. It illustrates the differences in the quality and accuracy of the data acquired using
- traditional survey methods (ground-based survey points); and
- drone-based survey methods.
Drone surveys are safer, faster, yield better quality data and are cheaper to undertake that traditional volumetric survey methods. They are a convenient way of providing the volumetric data needed to manage complex earth moving projects. The better quality data has effects throughout the project management process including the cost of the material, transport / haulage and labour used for the earthworks.
Studies into the Australian market uptake in drone technology has revealed that:
“around half of survey participants said data accuracy was a problem. Issues included lack of positional accuracy, incomplete data, images not being georeferenced, incorrect units, and gaps in coverage”
(Amirebrahimi et. al. 2018),
This Highlights the need for specialist operators with experience of both unmanned technology and survey to deliver benefits from the technology.
Beyond haulage calculations and logistics, drone surveys can provide value at all key project stages:
- Before works surveys can cover virgin ground to inform design, excavation, permit requirements and siting information.
- During works surveys can be used for safety audits, progress tracking, logistics and compliance, and,
- After construction surveys can ensure contractor compliance with the design specification and inform the as-built design.
Drone survey is being embraced by the construction industry. It is overtaking traditional survey methods by consistently delivering better quality data faster, safer and more economically than traditional survey techniques.
If you would like to learn more about how you can incorporate drone surveys into your next project, please contact us.
Amirebrahimi, S., Quadros, N., Coppa, I. and Keyser, J., 2018. UAV data acquisition in Australian and New Zealand. FrontierSI
Julge, K., Ellmann, A. and Köök, R., 2019. Unmanned Aerial Vehicle Surveying For Monitoring Road Construction Earthworks. The Baltic Journal of Road and Bridge Engineering, 14(1), pp.1-17.